[BUG] FTP save produces truncated/corrupt KDBX file – file gets smaller when adding entries

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• I have read the FAQ section, searched the open issues, and still think this is a new bug.

Describe the bug you encountered:

Description:
When saving the database to FTP after adding a new entry on the device, the uploaded file is truncated/corrupt. The file on the FTP server becomes smaller instead of larger. KeePassXC fails to open it with "Ungültige Größe der Inner-Header-ID" (Invalid inner header id size).

Expected behavior: The full database is uploaded; file size increases when adding data.

Actual behavior: Uploaded file is smaller and unreadable by KeePassXC.

Analysis (from code review):
In CachingFileStorage.cs (UpdateRemoteFile) and NetFtpFileStorage.cs (TransactedWrite.CommitWrite, UntransactedWrite.CommitWrite), the FTP upload stream is closed without calling Flush() first. FTP streams can buffer data; without Flush(), the transfer may complete before all buffered data is sent, resulting in a truncated file.

Suggested fix:
Add remoteStream.Flush() before remoteStream.Close() in:

• CachingFileStorage.cs line 364
• NetFtpFileStorage.cs TransactedWrite.CommitWrite (before _stream.Close())
• NetFtpFileStorage.cs UntransactedWrite.CommitWrite (before _stream.Close())

Environment: Android, FTP (Kasserver), KeePass2Android latest

References: Similar issue with FluentFTP OpenWrite: https://stackoverflow.com/questions/35558561/system-net-ftpclient-openwrite-doesnt-upload-file-unless-i-insert-a-sleep-before

Describe what you expected to happen:

No response

What version of Keepass2Android are you using?

1.14-r4

Which version of Android are you on?

16

Start in CachingFileStorage.cs at UpdateRemoteFile and in NetFtpFileStorage.cs at TransactedWrite.CommitWrite and UntransactedWrite.CommitWrite. Review how each FTP stream is closed, then verify that the full database upload completes before the stream is closed and that the resulting KDBX file is no longer truncated.